488 mkii tape speed problems

Discussion in 'TASCAM DIY Repairs and Mods' started by tross1024, Aug 15, 2013.

  1. tross1024

    tross1024 New Member

    Joined:
    Aug 2013
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    Gear:
    244 424mkii 488mkii
    Hi everyone,
    Long story short: Currently my 488 mkII is playing slower than it was before. My gut feeling is that its the belt. When I hit play, the tape speed will start out fast and then over the next 10 seconds slow down to a constant speed, not extremely slower than normal, but definitely not normal. While its playing, if I take a pen and lightly pull the pinch roller mechanism away from the tape and capstan shaft (not enough to terminate friction altogether), the speed returns to normal. But as soon as I let go it slows down again. I also noticed that the pitch controller is much less responsive when I increase the pitch as opposed to when I decrease. If I quickly turn the pitch control all the way to the right, it takes several seconds for the pitch to slowly speed up, whereas if I quickly turn it all the way to the left it immediately slows down. So, It seems like the normal resistance of the pinch roller against the capstan shaft is actually slowing the capstan shaft down. Could this be due to a stretched belt? Seems like a stretched belt could account for the lagging. I recently took tape mechanism apart and its possible I could have put a little strain on the belt when detaching the motor. But I can't really say for sure until I replace the belt. Anyone have any thoughts or seen these symptoms before?
  2. wkrbee

    wkrbee Active Member

    Joined:
    Sep 2012
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    From:
    Outside the Emerald City
    Capstan belt
  3. Christopher Harvey

    Christopher Harvey New Member

    Joined:
    May 2014
    Messages:
    2
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    0
    Gear:
    Tascam 488 Mkii
    if not a belt problem perhaps cleaning solution has washed the lubrication out of the oil impregnated capstan bearing that the shaft protrudes up thru... a drop of machine oil from a sowing needle at the base of the capstan shaft might help...and when cleaning press the swab pinching in a paper towel or such to remove excess solution so as to not run down the capstan shaft thru the bearing
    i see this post is old and is probably no longer an issue ...i am trying to obtain a replacement belt for mine
    good luck, (caveman) Christopher Harvey